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Offsets and polarization at strained AlN/GaN polar interfaces

Fabio Bernardini·Vincenzo Fiorentin·David Vanderbilt
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Abstract

The strain induced by lattice mismatch at the interface is responsible for the different value of the band discontinuities observed recently for the AlN/GaN (AlN on GaN) and the GaN/AlN (GaN on AlN) polar (0001) interface. We present a first-principles calculation of valence band offsets, interface dipoles, strain-induced piezoelectric fields, relaxed geometric structure, and formation energies. Our results confirm the existence of a large forward-backward asymmetry for this interface.

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Fabio Bernardini, Vincenzo Fiorentin, David Vanderbilt. 1996-12-11. Offsets and polarization at strained AlN/GaN polar interfaces. https://arxiv.org/abs/cond-mat/9612107

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